Entrainment and task co-representation effects for discrete and continuous action sequences

Abstract

A large body of work has established an influence of other people's actions on our own actions. For example, actors entrain to the movements of others, in studies that typically employ continuous movements. Likewise, studies on co-representation have shown that people automatically corepresent a co-actor's task, in studies that typically employ discrete actions. Here we examined entrainment and corepresentation within a single task paradigm. Participants sat next to a confederate while simultaneously moving their right hand back and forth between two targets. We crossed whether or not the participant and the confederate moved over an obstacle and manipulated whether participants generated discrete or continuous movement sequences, while varying the space between the actors and whether the actors could see each other's movements. Participants moved higher when the confederate cleared an obstacle than when he did not. For continuous movements, this effect depended on the availability of visual information, as would be expected on the basis of entrainment. In contrast, the co-actor's task modulated the height of discrete movements, regardless of the availability of visual information, which is consistent with co-representation. Space did not have an effect. These results provide new insights into the interplay between co-representation and entrainment for discrete-and continuous-action tasks.

Moving higher and higher: imitators’ movements are sensitive to observed trajectories regardless of action rationality

“…Despite this, participants’ movements between their own targets were higher after having observed the actor reach over obstacles to point to her targets, compared to when she moved with the same trajectory but there were no obstacles between her targets. This supports other work demonstrating that the proximity of the co-actor’s obstacle does not influence obstacle priming (van der Wel and Fu 2015 ).…”

“…Van der Wel and Fu ( 2015 ) proposed that for discrete movements obstacle priming is due to the co-representation of the actor’s task (Sebanz et al 2005 ). Conversely, for continuous movements obstacle priming is the result of entrainment and thus dependent on receiving concurrent visual information from a co-actor (Richardson et al 2005 ).…”

“…The mechanism behind obstacle priming was recently explored by van der Wel and Fu ( 2015 ) who aimed to investigate whether obstacle priming was the result of entrainment or co-representation of the model’s action (van der Wel and Fu 2015 ). Entrainment refers to the unintentional, rhythmical synchronisation of two individuals’ actions.…”

“…Whereas, co-representation involves symbolically representing the goals and intentions of the co-actor (Sebanz et al 2005 ). Van der Wel and Fu ( 2015 ) proposed that the mechanism may vary depending on the nature of the action.…”

“…For continuous movements, however, obstacle priming only occurred when participants could see the action of the confederate. Van der Wel and Fu ( 2015 ) argued that obstacle priming during continuous movements is due to entrainment and, thus, dependent on visual information; whilst during discrete movements, obstacle priming is driven by co-representation of the actor’s task.…”